Selective continuous-variable quantum process tomography

TL;DR

This paper introduces a protocol for selectively estimating specific elements of a continuous-variable quantum process in the position representation, enabling targeted characterization without full process reconstruction.

Contribution

It presents a novel adaptive protocol using controlled squeezing and translation for selective quantum process tomography in continuous variables.

Findings

Protocol allows selective estimation of process elements

Numerical simulations demonstrate partial process reconstruction

Method avoids full process tomography, saving resources

Abstract

Quantum process tomography is a useful tool for characterizing quantum processes. This task is essential for the development of different areas, such as quantum information processing. In this work, we present a protocol for selective continuous-variable quantum process tomography. Our proposal allows one to selectively estimate any element of an unknown continuous-variable quantum process in the position representation, without requiring the complete reconstruction of the process. By resorting to controlled squeezing and translation operations, and adaptatively discretizing the process, a direct measure of an estimate of any process element can be obtained. Furthermore, we show, supported by numerical simulations, how the protocol can be used to partially reconstruct on a region a continuous-variable quantum process.